This SSA (K05) application seeks salary support for the applicant to continue and build upon a long-standing (15 yr.) program of research into the neurophysiology of cocaine addiction in animal models. This award would reduce the applicant's teaching and administrative activities in all aspects of his academic pursuits that are not directly related to drug abuse. The candidate has recently taken the Chair of the Department of Cellular and Molecular Pharmacology at Chicago Medical School and is in the process of recruiting a group of researchers focused on the neurobiology of addiction. The first major goal of this SSA is to allow the applicant the necessary time to devote at least 75 percent effort to conducting and administering NIDA-related research activities. The second goal is to allow the applicant to continue the development of his own research program into new and powerful electrophysiological and cellular techniques including dual somatic and dendritic patch clamp recordings and ion imaging. Scientifically, the aims of this project are: 1) To characterize dopamine receptor modulation of somatic voltage-gated channels in both medium spiny neurons (MSNs) of the nucleus accumbens and pyramidal neurons (PNs) of the rodent (rat and mouse) prefrontal cortex (PFC). 2) To determine dopamine receptor modulation of dendritic voltage-gated channels in PFC PNs. 3) To characterize the effects of repeated cocaine self-administration on somatic and dendritic voltage-gated channels. Hopefully, these studies will identify specific neuroadaptations that accompany and perhaps cause cocaine addiction and drug-seeking behavior.